I don't see 80 I see Uryu recovering 75 which is normal if he has at least 100% critical, it applies to fury recovery 50 x 1.5 = 70

Concerning the damage, you are victim of Askin mods combined with RJ defense boost + Uryu own mod that a LOT of defense and avoid injury rate

HP recovery is from Valkyrie death mod

All in all the bugs are only visuals I think, SDT skill works but the ice is broken by your Muken subsequent attack but ice keeps on display, Valkyrie is killed by Muken but still displayed on screen. those are well known bugs they never bothered to correct